JP2011005799A - Method and device for cooling management of coarse aggregate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for the cooling management of a coarse aggregate capable of bringing the coarse aggregate into a sufficiently usable state by cooling it to 18-22°C even in summer.SOLUTION: In an aggregate storage facility with a plurality of aggregate bottles 1 arranged in parallel for storing and discharging the fine and coarse aggregate at each particle size group, three aggregate bottles 1(1a, 1b, 1c) are prepared at each particle size group to store and discharge the coarse aggregate, and an operation is repeated by a one-day time lag to the three aggregate bottles 1a, 1b, 1c thereby one bottle per day of each coarse aggregate classified in each particle size group is cooled to be usable. The operation is composed of two-day processing work which cools the coarse aggregate to a temperature of 18-22°C by filling a one-day use amount of the coarse aggregate to an empty aggregate bottle and sprinkling cooling water to the aggregate and suspending the sprinkling of water to drain the aggregate. A process on a third day to discharge the coarse aggregate from the aggregate bottle is repeated.

Description

  The present invention belongs to the technical field of cooling coarse aggregates in aggregate bins, and more specifically, a plurality of aggregate bins for storing and discharging coarse aggregates and fine aggregates for each particle size group. The present invention relates to a cooling management method and a cooling management device for coarse aggregate in an aggregate storage facility.

In concrete dam construction work, mass concrete is generally manufactured by providing the aggregate storage facility at a construction site. Aggregates may be collected / manufactured on site or purchased, but in any case aggregates are stocked at the construction site.
The aggregate storage facility is provided in the vicinity of a concrete plant, and with the production of concrete, the aggregate divided into predetermined particle size groups from the lower end of the aggregate bin is discharged using a vibration feeder or a cut gate ( Drawer) and a belt conveyor, and are supplied to the uppermost aggregate bin (top bin) of the concrete plant.

By the way, in the concrete dam construction work, when the concrete driving temperature exceeds 25 ° C., the driving is prohibited. The peak temperature after concrete pouring reaches about 40-50 ° C, and the difference from the final stable temperature increases, so the amount of shrinkage also increases, and as a result, the possibility of cracking increases. This is because the quality of the product (as a product) decreases.
Therefore, especially in the summer, there is a period when it is necessary to suspend concrete placement, and there is a problem of worker's suspension of work, unnecessary loss of equipment and machinery, and an increase in expenses due to postponement of the construction period. It was necessary to take some measures.

Therefore, conventionally, inventions have been disclosed in which aggregates used as raw materials for concrete are cooled by various methods (see, for example, Patent Documents 1 to 4).
Among these, the invention according to Patent Document 4 is a technique for cooling the aggregate in the aggregate bin with cooling water, and has a simple configuration and precision compared with the inventions according to other Patent Documents 1 to 3. There is an advantage that it is not necessary to introduce a machine, the equipment cost is low, there is no breakdown, and it can be implemented economically.
Specifically, in the invention according to Patent Document 4, a pair of (two) bones each having a plurality of parts for receiving, storing, and discharging aggregates divided into predetermined particle size groups and having top ends as open ends are provided. This is an aggregate cooling device that cools aggregates by heat exchange with cooling water in the aggregate bins, and by continuously using a pair of aggregate bins prepared for each predetermined particle size group, continuous operation work (Refer to claims 1 and 2 of the document 1).

Japanese Patent Laid-Open No. 6-182752 JP-A-6-198635 JP-A-10-329129 JP-A-7-167542

  Although the invention according to Patent Document 4 has a temporary effect that the driving efficiency can be increased as compared with the case where the aggregate bin is classified into one bin per aggregate (one division), the bone is recognized. There was a fatal problem in which the temperature adjustment of the aggregate was not taken into account at all, for example, the top of the material bin was carried out at an open end exposed to direct sunlight.

That is, in order for the concrete placing temperature not to exceed 25 ° C., it is necessary to cool the coarse aggregate until it falls within the range of 18 to 22 ° C. when discharged from the aggregate bin.
Since the invention which concerns on patent document 4 is the structure which drives an aggregate bin by 2 bins alternately per aggregate 1 class, the process of filling an aggregate in 1 day per bin, sprinkling cooling water The above three steps of the cooling process and the draining process must be surely completed to prepare for placing concrete on the next day.
According to the experiment results by the present applicant, in order to keep the temperature of the coarse aggregate within the range of 18 to 22 ° C., the amount of coarse aggregate used per day (about 70 to 150 m ³ ) is used. Even if it exists, it takes about 5 to 10 hours for the step of filling the aggregate, it takes about 20 hours for the step of spraying the cooling water and cooling it, and about 4 to 8 hours for the step of draining. I know it. In the case of fine aggregate, since the particle size is further smaller than that of coarse aggregate, it takes time to further drain the water.

Therefore, according to the invention according to Patent Document 4, even if a roof material that blocks direct sunlight is provided at the top, the temperature of the aggregate (coarse aggregate, fine aggregate) is set to 18 in one day per bottle. It is impossible to cool and use within the range of ˜22 ° C. in terms of time, and driving is prohibited in the summer, resulting in the various problems described above.
As mentioned above, the problem in the case of alternately operating a pair of aggregate bins every day has been pointed out. For example, a pair of aggregate bins are filled together with coarse aggregates for two days per bin. When the engine is operated alternately in two days, even if the coarse aggregate used on the first day can be cooled, the coarse aggregate used on the second day needs to be cooled again and drained. Since the work takes more than one day, it is unreasonable, and again it is prohibited to drive in the summer, resulting in the various problems described above.

As a reference example, a heat balance calculation result performed by the present applicant is shown in FIG. Referring to the left column [conventional case], as a result of watering for 8 hours for 300 m ³ of 26 ° C. coarse aggregate filled in the roofed aggregate bin, the cooled coarse aggregate was 24.6 ° C. The concrete (driving) temperature is 25.4 to 25.8 ° C. Therefore, water spraying for about 8 hours is over 25 ° C, so it is prohibited to drive in the summer.

  The object of the present invention is to have a simple configuration, to reduce the cost of equipment without introducing a precision machine, to be economically implemented with few breakdowns, and to reduce the temperature of the coarse aggregate even in summer. The object of the present invention is to provide a cooling management method and a cooling management device for coarse aggregate, which can be cooled to -22 ° C to be sufficiently usable.

As a means for solving the problems of the background art, the cooling management method for coarse aggregate according to the invention described in claim 1 is:
A coarse aggregate cooling management method in an aggregate storage facility comprising a plurality of aggregate bins for storing and discharging coarse aggregate and fine aggregate for each particle size group,
Prepare at least three aggregate bins for storing and discharging coarse aggregate,
Filling empty aggregate bins with the amount of coarse aggregate to be used per day, spraying the coarse aggregate with cooling water, cooling it, stopping the water spray and draining it over several days And the step of cooling the coarse aggregate to 18-22 ° C. and then discharging the coarse aggregate from the aggregate bin is repeated for each of the at least three aggregate bins, shifted by one day. Thus, the coarse aggregate divided into the particle size groups is cooled so that one bottle can be used every day.

According to a second aspect of the present invention, there is provided a coarse aggregate cooling management method comprising: a plurality of aggregate bins that store and discharge coarse aggregates and fine aggregates for each particle size group; An aggregate cooling management method comprising:
Prepare three aggregate bins for storing and discharging coarse aggregates for each particle size group,
It takes 2 days to fill the empty aggregate bin with the amount of coarse aggregate to be used for one day, spray the cooling water on the coarse aggregate and cool it, and stop the water spray and drain the water. The process of cooling the coarse aggregate to 18-22 ° C. and discharging the coarse aggregate from the aggregate bin on the third day is repeated for each of the three aggregate bins by shifting by one day. By performing, it cools so that the coarse aggregate divided for every particle size group can be used one bottle every day.

  The invention described in claim 3 is the coarse aggregate cooling management method according to claim 1 or 2, wherein the coarse particle size groups are group 1 (150 mm to 80 mm), group 2 (80 to 40 mm). , Group 3 (40 to 20 mm), Group 4 (20 to 5 mm), or four particle size groups, or Group 3 to 4 particle size groups.

  According to a fourth aspect of the present invention, in the cooling management method for coarse aggregate according to any one of the first to third aspects, the cooling water is cooled to about 5 ° C. and 20 to 50 liters per minute. It is characterized by watering at a rate of.

  Invention of Claim 5 is the cooling management method of the coarse aggregate as described in any one of Claims 1-4. The operation | work which sprinkles cooling water to the said coarse aggregate is performed for 20 to 30 hours. It is characterized by that.

According to a sixth aspect of the present invention, there is provided a coarse aggregate cooling management apparatus comprising a plurality of aggregate bins for storing and discharging coarse aggregates and fine aggregates for each particle size group. An aggregate cooling management device comprising:
At least three aggregate bins for storing and discharging the coarse aggregate are provided for each predetermined particle size group, and each of the aggregate bins is provided with a roof material having a filling port at the top end portion. A watering device is attached to the lower surface of the roofing material,
An empty aggregate bin is filled with the amount of coarse aggregate to be used per day, and the coarse aggregate is sprayed with cooling water and cooled, and the water spray is stopped and drained. It is possible to use coarse aggregates classified by particle size group one by one every day by repeatedly performing the above-mentioned at least three aggregate bins by shifting by one day so that the temperature is cooled to 18-22 ° C. It is cooled.

The coarse aggregate cooling management method and cooling management device according to the present invention have the following effects. 1) Three aggregate bins provided in an aggregate storage facility are prepared for each predetermined particle size group, and an empty aggregate bin 1 is filled with a coarse aggregate in an amount to be used for one day. The cooling water is sprayed and cooled, and the operation until the watering is stopped and drained is performed over 2 days. The temperature of the coarse aggregate is cooled to 18 to 22 ° C., and the aggregate on the third day. The step of discharging the coarse aggregate from the bin is repeated for each of the three aggregate bins 1a, 1b, and 1c by shifting by one day, so that the coarse aggregate according to each particle size group is set to 18 to 22 ° C. One bottle per day can be continuously used in a cooled state.
Therefore, since the concrete pouring temperature does not exceed 25 ° C. (see the right column in FIG. 3 as an example), the concrete placement work can be performed in the same manner as in other periods even in summer. Therefore, there is no need to suspend the placement of concrete, there is no problem of worker's suspension of work, no waste of equipment and machinery is generated, and there is no increase in expenses due to postponement of construction period. And a cooling management method and a cooling management device for a rough aggregate can be provided.
2) As a secondary effect, when purchasing aggregates, since the aggregates on the market are dry manufacturing, a considerable amount of stone powder adheres to the surface, which improves the fresh properties of concrete and the quality after hardening. affect. If the amount of stone powder increases, the amount of unit water required also increases, and the specified slump cannot be obtained with the unit water amount of the indicated composition. Increasing the unit water volume to obtain a slump decreases the strength. Moreover, drying shrinkage also becomes large and it causes a surface crack. However, it is possible to wash away the stone powder adhering to the surface by directly spraying sufficient cooling water on the coarse aggregate, which can greatly contribute to the improvement of the quality of the concrete.

It is the elevation which showed roughly the cooling management method and cooling management device of the coarse aggregate which concern on this invention. FIGS. 8A to 8C are elevation views showing in a stepwise manner a predetermined work process performed on three aggregate bins prepared for each particle size group. It is the table | surface which showed the heat balance calculation result which contrasted the conventional case and the case of a present Example.

  Next, an embodiment of a cooling management method and a cooling management device for coarse aggregate according to the present invention will be described with reference to the drawings.

1 and 2 show an embodiment of a coarse aggregate cooling management method and cooling management apparatus according to the present invention.
The cooling management method for coarse aggregate according to the present invention includes a method for managing coarse aggregate in an aggregate storage facility 10 in which a plurality of aggregate bins 1 for storing and discharging coarse aggregate and fine aggregate for each particle size group are arranged in parallel. It is a cooling management method, three aggregate bins 1 for storing and discharging coarse aggregate are prepared for each particle size group,
Fill the empty aggregate bin 1 with the amount of coarse aggregate to be used per day, spray cooling water on the coarse aggregate and cool it, stop the water spray and drain the water for 2 days. The step of cooling the coarse aggregate temperature (surface temperature) to 18-22 ° C. and discharging the coarse aggregate from the aggregate bin 1 on the third day is performed on the three aggregate bins 1. On the other hand, it is characterized by cooling the coarse aggregate divided by the particle size group so that it can be used one by one every day by repeatedly performing it by shifting by one day.

The aggregate storage facility 10 is usually provided in the vicinity of a concrete plant (not shown), and vibrates coarse aggregate divided into predetermined particle size groups from the lower end of the aggregate bin 1 as concrete is produced. The material is discharged using a feeder or a cut gate, and is supplied to the uppermost aggregate bin (top bin) of the concrete plant by the belt conveyor 11.
A known aggregate bin can be applied to the configuration of the aggregate bin. As described above, the coarse aggregate is discharged using a known vibration feeder or cut gate. In addition, in order to block the intrusion of the cooling water dripping from the adjacent aggregate bin 1, a device such as providing a drainage side groove or raising the discharge port 3 itself by about several centimeters is appropriately performed.

The coarse aggregate has four particle sizes of group 1 (150 mm to 80 mm), group 2 (80 to 40 mm), group 3 (40 to 20 mm), and group 4 (20 to 5 mm) depending on the particle size. They are roughly divided into groups and are stored in the aggregate bin 1 for each particle size group.
Depending on the structural design of the concrete dam to be constructed, such as the strength and size of the concrete dam, all the coarse aggregates of the four granular groups of groups 1-4 may be used, or the three granularities of the groups 2-4. In some cases, a group of coarse aggregates may be used, and the combination of particle size groups can be appropriately selected according to the structural design. Incidentally, as shown in FIG. 1, the aggregate storage facility 10 according to the present embodiment shows the usage status of the coarse aggregate divided into the three particle size groups of the groups 2 to 4.

In the cooling management method according to the present invention, the aggregate bin 1 in which the coarse aggregate is divided and stored for each particle size group is further divided into three for each particle size group, and a predetermined process is performed. A device has been devised that can continuously supply coarse aggregate cooled to a temperature (18-22 ° C.) appropriate for placing concrete.
Hereinafter, the work process performed with respect to the aggregate bin 1 prepared for every three particle size groups (group 2-4 in a present Example) is demonstrated concretely.

FIGS. 2A to 2C show, as an example, work steps for three identically sized aggregate bins 1 (1a, 1b, 1c) that store and discharge the group 2 (particle size: 80-40 mm) particle size group. Shown step by step.
Incidentally, FIG. 2A shows the first day, FIG. 2B shows the second day, and FIG. 2C shows the third day. In describing the work process step by step, the central aggregate bin 1b among the three aggregate bins will be mainly described.

The aggregate bin 1b of FIG. 2A shows a stage in which the amount of coarse aggregate to be used per day is filled through the upper filling port 2 from an empty state where all of the coarse aggregate is discharged the previous day. The same applies to the aggregate bin 1a in FIG. 2B and the aggregate bin 1c in FIG. 2C.
The size of the aggregate bin 1b is about 70~150m ³ (in this example 100 m ³⁾ is carried out at, roofing is provided for shielding direct sunlight on its top. The roof material can be integrated with the aggregate bin or can be detachable.
The filling operation is usually performed during the day, and the filling operation takes about 5 to 10 hours using a transport vehicle such as a dump truck. After finishing the filling operation, the watering operation is usually started as shown in FIG. 2B from the night of the first day to the second day.

The aggregate bin 1b of FIG. 2B shows a stage in which cooling water is sprinkled on the coarse aggregate to cool it. The same applies to the aggregate bin 1a in FIG. 2C and the aggregate bin 1c in FIG. 2A.
The temperature of the cooling water is about 5 to 8 ° C. (5 ° C. in this embodiment), and is about 20 to 50 liters per minute (40 liters in this embodiment) for about 20 to 30 hours (this embodiment). Then, water is sprinkled to cool the coarse aggregate to 18-22 ° C. These figures are based on trial calculations and experiments by the applicant. The cooling water temperature is preferably as low as possible. In addition, the watering amount and watering time are appropriately designed within the range of the above numerical values according to various conditions such as the size of the aggregate bin 1b and the filling amount of the coarse aggregate as well as the weather and temperature at the site. Be changed.

In the present embodiment, the apparatus for spraying the cooling water is implemented by a shower ring apparatus in which a tank and a storage tank are provided outside, and a plurality of spraying devices are attached to the lower surface of the roofing material in a well-balanced manner. In addition, the watering means is not limited to this, and a known watering means such as drawing a hose material from the outside to sprinkle water on the condition that the cooling water uniformly hits the upper part of the filled coarse aggregate. Can be implemented.
The cooling water that has evenly dropped on the coarse aggregate by the showering device and has flowed down is dripped downward through the drainage port 3. Therefore, during the process of sprinkling the cooling water and performing the cooling process, and the subsequent draining process, a sliding drainage gutter is provided directly below the drainage port 3 to avoid the cooling water falling on the belt conveyor. Keep in mind that
The temperature of the coarse aggregate in the aggregate bin 1b is roughly estimated by the applicant's trial calculation and the relationship between the amount of coarse aggregate filled and the watering time based on the experiment. It can also be implemented by providing a sensing sensor.
In addition, when the temperature of the coarse aggregate decreases earlier than a predetermined time due to the weather conditions at the site, the watering operation is normally continued until the time required for draining treatment.

Thus, after performing the watering operation for about 20 to 30 hours from the night of the first day, the coarse aggregate is cooled to a temperature of 18 to 22 ° C., and then the watering operation is stopped. Drain the water from midnight to early morning on the third day. By the way, the draining process here refers to simply stopping the watering operation.
Based on trial calculations and experiments by the present applicant, the time required for draining treatment is about 4 to 5 hours in the case of the coarse aggregate of group 2 (particle size: 80 to 40 mm) according to FIG. Yes. Therefore, the water spraying operation is stopped at least 4 to 5 hours before the coarse aggregate is discharged on the third day, and the operation is switched to the draining process.
In addition, since the draining process is usually performed from midnight to early morning, there is little possibility that the temperature of the coarse aggregate will rise unduly during that time. However, in order to reliably maintain 18 to 22 ° C., an aggregate bin is used according to weather conditions and the like. A device such as installing a cold water bottle on the outer periphery of 1b or spraying cooling water on the aggregate bin 1b itself is appropriately performed.

The aggregate bin 1b in FIG. 2C shows a stage in which the coarse aggregate after the draining process is discharged to the outside intermittently or collectively over a predetermined time for placing concrete. The same applies to the aggregate bin 1a in FIG. 2A and the aggregate bin 1c in FIG. 2B.
When discharging the coarse aggregate, the sliding drainage culvert is slid to avoid it, and the coarse aggregate cooled to 18 to 22 ° C. is discharged using a vibration feeder or a cut gate to convey the belt conveyor 11. And is supplied to the aggregate bin (top bin) at the top of the concrete plant by the belt conveyor 11.

  Therefore, as described above, the coarse aggregates related to the three aggregate bins 1 (1a, 1b, 1c) that store and discharge the particle size group of the group 2 (particle size: 80 to 40 mm) according to the present embodiment. According to the cooling management method, an empty aggregate bin 1 is filled with an amount of coarse aggregate to be used for one day, and the coarse aggregate is sprayed with cooling water and cooled, and the water spray is stopped and drained. The process until the processing is carried out over 2 days, the temperature of the coarse aggregate is cooled to 18-22 ° C., and the coarse aggregate is discharged from the aggregate bin on the third day. By repeatedly shifting the bottles 1a, 1b, and 1c one day at a time, the coarse aggregates related to the particle size group of Group 2 (particle size: 80 to 40 mm) are cooled to 18 to 22 ° C. every day. The bottle can be used continuously.

For reference, the heat balance calculation results according to this example are shown in the right column of FIG. According to the present example, as a result of watering for 24 hours to 100 m ³ of 26 ° C. coarse aggregate filled in the aggregate bin 1b, the cooled coarse aggregate can be lowered to 19.3 ° C., and thereafter The concrete (driving) temperature of 22.3 to 23.4 ° C. Therefore, since it is less than 25 ° C., the concrete can be sufficiently placed even in summer.

The above is a description of the particle size group of group 2 (particle size: 80 to 40 mm), but the particle size group of group 3 (40 to 20 mm) and group 4 (20 to 5 mm) according to FIG. By carrying out the above process at the same time, the coarse aggregate cooled to 18 to 22 ° C. can be continuously used one by one daily.
In addition, since the particle size group of group 3 (40-20 mm) and group 4 (20-5 mm) is smaller than the particle size group of group 2 (particle size: 80-40 mm), the watering time is 2 The target value is reached even if it is about 3 hours shorter. On the other hand, since the draining time needs to be increased by 2 to 3 hours, the total required time is almost the same.

As described above, the embodiments have been described with reference to the drawings. However, the present invention is not limited to the illustrated examples, and a range of design changes and application variations that a person skilled in the art normally performs without departing from the technical idea thereof. It is mentioned just in case that it contains.
For example, although the present Example demonstrated the aggregate storage facility using the coarse aggregate divided into the three particle size groups of the said groups 2-4, it is not limited to this, Four of the said groups 1-4 The same can be applied to an aggregate storage facility that uses coarse aggregates divided into particle size groups. Of course, although the scale becomes large, the same can be applied to an aggregate storage facility using coarse aggregates divided into five or more particle size groups.
In this embodiment, the three aggregate bins 1 (1a, 1b, 1c) are efficiently and rationally performed for each particle size group, but the coarse aggregate filling time, cooling processing time, It is also possible to use four or more aggregate bins 1 by further increasing the draining time. As an example, when four aggregate bins are used, an empty aggregate bin is filled with an amount of coarse aggregate used for one day, and the coarse aggregate is sprinkled with cooling water to be cooled. The process of stopping the operation and draining it over 3 days, cooling the temperature of the coarse aggregate to 18-22 ° C., and discharging the coarse aggregate from the aggregate bin on the fourth day, The four aggregate bins are repeatedly shifted by one day.

1 (1a, 1b, 1c) Aggregate bin 2 Filling port 3 Discharge port 4 Sliding drainage basin 10 Aggregate storage facility 11 Belt conveyor

Claims (6)

A coarse aggregate cooling management method in an aggregate storage facility comprising a plurality of aggregate bins for storing and discharging coarse aggregate and fine aggregate for each particle size group,
Prepare at least three aggregate bins for storing and discharging coarse aggregate,
Filling empty aggregate bins with the amount of coarse aggregate to be used per day, spraying the coarse aggregate with cooling water, cooling it, stopping the water spray and draining it over several days And the step of cooling the coarse aggregate to 18-22 ° C. and then discharging the coarse aggregate from the aggregate bin is repeated for each of the at least three aggregate bins, shifted by one day. Thus, the coarse aggregate cooling management method is characterized in that the coarse aggregate divided into each particle size group is cooled so that one bottle can be used every day. A coarse aggregate cooling management method in an aggregate storage facility comprising a plurality of aggregate bins for storing and discharging coarse aggregate and fine aggregate for each particle size group,
Prepare three aggregate bins for storing and discharging coarse aggregates for each particle size group,
It takes 2 days to fill the empty aggregate bin with the amount of coarse aggregate to be used for one day, spray the cooling water on the coarse aggregate and cool it, and stop the water spray and drain the water. The process of cooling the coarse aggregate to 18-22 ° C. and discharging the coarse aggregate from the aggregate bin on the third day is repeated for each of the three aggregate bins by shifting by one day. A cooling management method for coarse aggregate, characterized in that the coarse aggregate divided into each particle size group is cooled so that one bin can be used every day.   The coarse aggregate particle size groups include group 1 (150 mm to 80 mm), group 2 (80 to 40 mm), group 3 (40 to 20 mm), and group 4 (20 to 5 mm), or the group 2 The coarse aggregate cooling management method according to claim 1 or 2, wherein the three particle size groups of -4 are used.   The cooling water cooling method according to any one of claims 1 to 3, wherein the cooling water is cooled to about 5 ° C and sprayed at a rate of 20 to 50 liters per minute. .   The method of cooling management of a coarse aggregate according to any one of claims 1 to 4, wherein the operation of sprinkling cooling water on the coarse aggregate is performed for about 20 hours to 30 hours. A coarse aggregate cooling management device in an aggregate storage facility in which a plurality of aggregate bins for storing and discharging coarse aggregate and fine aggregate for each particle size group are arranged,
At least three aggregate bins for storing and discharging the coarse aggregate are provided for each predetermined particle size group, and each of the aggregate bins is provided with a roof material having a filling port at the top end portion. A watering device is attached to the lower surface of the roofing material,
An empty aggregate bin is filled with the amount of coarse aggregate to be used per day, and the coarse aggregate is sprayed with cooling water and cooled, and the water spray is stopped and drained. It is possible to use coarse aggregates classified by particle size group one by one every day by repeatedly performing the above-mentioned at least three aggregate bins by shifting by one day so that the temperature is cooled to 18-22 ° C. A coarse aggregate cooling management device characterized by being cooled.

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